Dispositions Introduced in Joining Elements for Strips to Form Floor Covering

ABSTRACT

The present invention relates to joining elements for strips made of solid wood, or plywood, or pressed wood, or synthetic material, with decorative finishing or not, forming a board to cover a subfloor, in which a triangular salience ( 1 ) or tongue element part of a strip (R), which longitudinally constitutes, on its upper end ( 2 ), a symmetric acute angle of about 45°, fits in a triangular groove ( 3 ) element in an acute angle belonging in the subsequent strip, which longitudinally constitutes on its internal and upper portion ( 4 ) a symmetric acute angle of about 45°, and so on, until a board to cover the subfloor is formed. Each strip (R) has, on a longitudinal side and on a transversal top, a triangular salience ( 1 ), and on the other longitudinal side and on the other transversal top, a triangular groove ( 3 ).

The present utility model patent relates to constructive dispositions introduced in joining elements for strips made of solid wood, or plywood, or pressed wood, or synthetic or any other material, with decorative finishing or not, forming a board to cover a subfloor.

As it is of common knowledge, there are subfloors composed of a wood beam structure, over which planks are nailed, forming the flooring itself.

In another art, there are subfloors composed of concrete slabs, covered with blocks or parket forming the flooring itself. The blocks or parket are usually applied over the concrete subfloor with the use of tar or glue, and after they are laid, sanding is performed in order to correct level differences. Varnishing is the next step, which procedure is allowed only in the installation site, and it shall be observed that, concerning blocks or parket, as in any other flooring not provided with tongue and groove elements on the four edges, there is the inconvenience that the product varnishing or final finishing may not be previously and industrially performed, due to the difference of level between the blocks or parket.

There are strips or floorings intended to cover subfloors, also known as solid wood floors, which comprise two or more strips joint laterally or on the four edges by the conventional system named tongue (T) and groove (G) fittings. However, such strips are usually made between as about 7 and 25 mm thick, with the most common strip, the 19-mm thick one, featuring upper surface useful for wear (SD) of about 6 mm, as shown on FIG. 1. It may also be observed, by way of example, that a 7-mm thick strip has an upper surface useful for wear (SD) of only about 3 mm, as shown on FIG. 2. Such thickness/wear parameters are known worldwide.

In a more modern art, there are the worldwide known “floating floors”, which are neither glued by overlaying nor nailed, comprising boards composed of solid wood, or plywood, or high-density wood planks, each board featuring tongue and groove-type fittings. In order to form and lay the “floating floor” or flooring itself, glue is applied to the strips edges, thus, as many boards as required to cover an environment are laterally and successively glued, the set of boards becoming a single floor, which is named “floating” because it remains simply laid on the concrete subfloor. This is an advantageous aspect, as it allows the floating floor expansion, caused by humidity and temperature differences. However, between the “floating floor” and the subfloor, an intermediate material is placed, intended to minimize noise caused by users walking, which is the worst inconvenience of “floating floors”, making such noises disturbing where the floor is installed and also to people in the next lower floor. Such intermediate material may be felt, rubber, cork, polyester foam, plastic or other insulating materials, and said material is easy to apply, as it is simply distributed over the subfloor before the flooring is laid. Nevertheless, none of said intermediate material features the appropriate solution, as the cost of the most efficient ones is similar to the cost of the floor itself, making the set excessively expensive, limiting sales in the market.

It is convenient to mention document number WO 97/47834, date of international publication Dec. 18, 1997, showing on the cover sheet the figure of a strip profile with tongue and groove elements. It shall be observed that this most recent technology is applicable to “floating floors”, and such tongue and groove elements in said patent were conceived with constructive features aiming mainly at facilitating assembling and disassembling a board or flooring, not using glue on the strips edges, exactly to allow the previously said disassembly without damages. Such technology is known in the art as “click” system. However, such technology is limited to raw material that allows fine milling for the strips, and it may be observed that, after that kind of “floating floor” with “click” system is assembled, the floor produces, in addition to the noises mentioned above, extra noises from the “click” system joints.

Another important inconvenience in the constructive dispositions with tongue and groove elements in said patent WO 97/47834, is that the “click” system manufacturing requires the use of a higher volume of raw material to obtain the same useful square area as traditional tongue and groove elements. That is because the strip has been conceived featuring the regular-sized tongue (T) element on one side and on the opposite side, an excessive lower projection (P), which is an extension of the groove (G) element cavity base, which projection (P) spends twice as much material as the material used in the tongue (T) element, while the other groove conventional fittings do not require any excessive material. By way of a clearer explanation, FIG. 3 is annexed, which is a section view of the strip shown on patent WO 97/47834 cover sheet. It is also important to emphasize that the system referred makes application difficult on strips under about 6 mm thick, and also on strips under about 100 mm wide, because the excessive material from the groove element (F) is fixed. Therefore, the narrower a strip, the higher the material loss percentage. As a result, the “click” system use is impractical for narrow strips.

The disposition introduced in joining elements for strips forming flooring for subfloors, object of this patent, have been secretly idealized and conceived to remedy the inconveniences described in the state of the technique report, comprising the disposition proposed in the inventive act resulting in functional improvement with significant material, tooling and electrical power saving, in which, the joining elements are, essentially, a triangular salience or tongue element part of a strip which longitudinally constitutes, on its upper end, a symmetric acute angle of about 45°, and said triangular salience fitting in a triangular groove element in an acute angle—belonging in the subsequent strip—which longitudinally constitutes in its internal and upper portion a symmetric acute angle of about 45°, and so on, until a board to cover the subfloor is formed. It shall be observed that each strip has, on a longitudinal side and on a transversal top, a triangular salience, and on the other longitudinal side and on the other transversal top, a triangular groove. The board so formed has a plain upper surface, with no difference in levels, overcoming the upper leveling accuracy of a board comprising strips with conventional tongue and groove elements.

Thus, considering the fitting described above, in one strip, high savings are obtained concerning the raw material usually required to manufacture strips with conventional fitting elements, because the joining elements, object of the present patent, allow to eliminate the lower portion of the groove element by using said triangular groove of about 45°, thus, the material to be applied to manufacture the groove element is transferred to the upper wear surface.

Thus, about fifty percent savings in material are obtained for a strip, when compared to the material which would be usually required to manufacture the strip with conventional fitting elements, because the joining elements object of the present patent allow, due to their constructive features, increasing the upper wear surface of a strip. As it has been mentioned above, for a 19-mm thick strip—see FIG. 1—made of solid wood, manufactured with conventional tongue and groove elements, the upper surface useful for wear (SD) is about 6 mm.

It is important to explain that the joining elements object of the present patent allow to manufacture a solid wood strip about only 3 mm. thick, while the strips provided with conventional tongue and groove elements are manufactured with minimal thickness about 7 mm.

It may also be observed that, in the present patent, the board formed by said strips may be glued over concrete subfloor, or glued and/or nailed over subfloors of plywood, or pressed wood, or other appropriate materials. The strips, both over concrete subfloors and on other subfloors are installed one be one, until the flooring is formed.

The present patent may be better understood in the light of the drawings commented below, comprising:

FIG. 4, showing an exploded section view of two strips (R) to be joined, to form a flooring to be applied over a subfloor. The Figure shows a triangular salience (1) or tongue element part of a strip (R), which longitudinally constitutes, on its upper end (2), a symmetric acute angle of about 45°, said triangular salience fitting in a triangular groove (3) or groove element in an acute angle—belonging in the subsequent strip—as shown on FIG. 5, which longitudinally constitutes on its internal and upper portion (4) a symmetric acute angle of about 45°, and so on, until a board to cover the subfloor is formed. It shall be observed that each strip (R) has, on a longitudinal side and on a transversal top, a triangular salience (1), and on the other longitudinal side and on the other transversal top, a triangular groove (3), as shown in the perspective in FIG. 8.

In order to make it more understandable, FIGS. 6 and 7 are annexed, showing the strip (R) profile with the joining elements (1, 3) of the present patent, on a solid wood strip (R) only 9.5 mm thick, obtaining the same upper surface useful for wear (SD) of about 6 mm, which is shown on FIG. 1, and getting savings of about fifty percent in raw material, either wood or other material. 

1. (canceled)
 2. A floor covering strip, comprising: an upper surface; a lower surface; a first transverse side having an edge; a second transverse side having an edge; a first longitudinal side having an edge, the edge consisting essentially of a substantially vertical portion, depending from the upper surface, and a triangular-shaped salience disposed below the vertical portion, the triangular-shaped salience forming an acute angle with respect to the vertical portion; and a second longitudinal side having an edge, the edge consisting essentially of a substantially vertical portion, depending from the upper surface, and a triangular-shaped groove disposed below the vertical portion, the triangular-shaped groove forming an acute angle with respect to the vertical portion and a complementary angle with respect to the triangular-shaped salience angle.
 3. The strip according to claim 2, wherein the acute angles of the triangular-shaped salience and groove are about 45°.
 4. The strip according to claim 2, wherein the vertical portions extend along about two-thirds of the height of each respective side.
 5. The strip according to claim 4, wherein the triangular-shaped salience and the triangular-shaped groove extend along about one-third of the height of each respective side.
 6. The strip according to claim 2, wherein the height of the respective sides is uniform and at least 3 mm.
 7. The strip according to claim 2, wherein the strip has a uniform thickness of about 9.5 mm, the vertical portions extend along about 6 mm of the respective sides, and the triangular-shaped salience and groove extend along the remainder of the respective sides.
 8. The strip according to claim 2, wherein the upper surface is a wear-resistant surface.
 9. The strip according to claim 2, wherein the strip is fixedly attached to a subfloor.
 10. The strip according to claim 2, wherein the first transverse edge consists essentially of a substantially vertical portion, depending from the upper surface, and a triangular-shaped salience disposed below the vertical portion, the triangular-shaped salience forming an acute angle with respect to the vertical portion.
 11. The strip according to claim 10, wherein the second transverse edge consists essentially of a substantially vertical portion, depending from the upper surface, and a triangular-shaped groove disposed below the vertical portion, the triangular-shaped groove forming an acute angle with respect to the vertical portion and a complementary angle with respect to the triangular-shaped salience angle.
 12. A floor system, comprising: a plurality of strips fixedly attached to a subfloor, each of the strips having an upper surface, a lower surface and a plurality of sides including at least two complementary edges, wherein a first complementary edge consists essentially of a substantially vertical portion, depending from the upper surface, and a triangular-shaped salience disposed below the vertical portion, the triangular-shaped salience forming an acute angle with respect to the vertical portion, and wherein a second complementary edge consists essentially of a substantially vertical portion, depending from the upper surface, and a triangular-shaped groove disposed below the vertical portion, the triangular-shaped groove forming an acute angle with respect to the vertical portion and a complementary angle with respect to the triangular-shaped salience angle.
 13. The floor system according to claim 12, wherein the acute angles of the triangular-shaped salience and triangular-shaped groove are about 45°.
 14. The floor system according to claim 12, wherein the vertical portions extend along about two-thirds of the height of each respective side, and the triangular-shaped salience and the triangular-shaped groove extend along about one-third of the height of each respective side.
 15. The floor system according to claim 12, wherein the height of the floor system is uniform and at least 3 mm.
 16. The floor system according to claim 12, wherein the floor system has a uniform thickness of about 9.5 mm, the vertical portions of the strips extend along about 6 mm of the respective sides, and the triangular-shaped saliences and the triangular-shaped grooves of the strips extend along the remainder of the respective sides.
 17. The floor system according to claim 12, wherein the upper surface is a wear-resistant surface.
 18. The floor system according to claim 17, wherein the plurality of strips are formed from wood and are fixedly attached to the subfloor using glue or nails.
 19. The floor system according to claim 12, wherein the plurality of strips are under about 6 mm in thickness.
 20. The floor system according to claim 19, wherein the plurality of strips are under about 100 mm in width.
 21. The floor system according to claim 12, wherein the plurality of strips do not form an interlocking click system. 